Hi there, tank's been cycled and is now fully stocked. When I did water test today Amm 0, Nitrate 10-12 and nitrites up 0.25. Do I just do a series of water changes to bring this back down. (need to get more ph tester but 5 days ago it was 7.2) using liquid test kit.

If over feeding causes a rise in nitrites then I'm pretty sure that's what I've done :( it's really hard to know how much is enough when u first start. I got frozen cubes of live food for them and give them that every other day and i think there's prob. 2 much food in 1 cube for the number of fish. feed them twice a day two dried foods, or one live & one dried, but it's not the number of times its the amount i think.

Also I'm a little worried I'm over stocked now, got two corys julii (that's what i was told they were) as a present and they went in tank yesterday.
63l tank, 30cm wide, 35cm high, 60cm long. (about 3months old now, not sure exactly)
fish (all young and not fully grown) - added to tank with gaps of over a week between species
3 cherry barbs
2 honey gouramis
6 cardinal tetras
and now also the 2 corys

Should I do water changes twice a week maybe with that many fish?

Fish all look happy enough, very active - even the corys, I always thought bottom feeders just lazed around ot the bottom munching all day or night they're really playful great to watch be sorry if I haven't the room to keep them.

Anyway I'm rambling now :) love talking about my fish - going out today to get little hidey place for corys and some sand

That's good to know. I've added a little sand area in the corner (cos I've got gravel) and hidey place (plant pot) for them. I've also put an air stone in. The other fish in tank are really easy going so I think they'll not feel 2 threatened, it kinda looks like they're getting it together the way they've been dancing around with eachother all day! think it might be a case of two's company three's a crowd at the mo anyway

I've done a 30% water change aswell today. Is it worth testing the water again now or wait til tomorrow? (really don't know if it makes a difference waiting).

Also I've got a lot of things in the tank which takes up room so that's why I thought I might not be able to get any more fish. I'll be posting an up to date pic soon

Your Nitrite will lower due to the biological filtration process, not simply because of water changes. I see no reason to change 30% daily simply because of a small Nitrite reading. Seriously, in your setup with your fish selections, a small temporary Nitrite reading is about as dangerous as a paper cut. You certainly aren't going to give yourself a paper cut on purpose, but you aren't going to call an ambulance either.